Only relatively recently have robotic applications also become of public interest in the field of surgery. In the case of surgical robots, the objective is not the exact repetition of programmed working sequences, since the movements which need to be performed are not repeated from one operation to the next. Unlike industrial robots, surgical robots are not therefore controlled by a fixed program; their movements are defined in each individual case by a surgeon controlling the robot who, whether with the naked eye or with the aid of a camera, observes the robot and its surgical field. In order to operate the robot, the surgeon is preferably provided with a computer-supported control device which is connected with the robot and the camera. In particular, applications in which the surgeon monitors the surgical field by means of a camera are of considerable technical and medical interest. On the one hand, they make it possible for experienced specialists to perform operations without needing to be present in the operating theatre themselves, and thus to treat patients in far distant locations without needing to travel. On the other hand, the camera is an effective means for the surgeon (who may also be present in the theatre) to obtain a view of the inside of the body during the course of a minimally invasive procedure. However, one problem with such operations is that, although the operating surgeon can observe the immediate surgical field by means of the camera and control a surgical instrument held by the robot, information on the wider operating environment, on movements of the auxiliary theatre staff who are present etc. is not accessible through direct sensory impressions. Rather, the operating surgeon's attention is focused on the monitor of the control device which displays the image transmitted by the camera and displays the contents of the control program. However, if the operating surgeon is not precisely aware of the shape of the robotic arm guiding the tool and its possible movements, in extreme cases this can lead to undesired contacts between the robotic arm and the patient's body and can in extreme cases lead to injuries.
Another possible application for robot systems in the operating theatre is to assist a surgeon who is personally present, for example by holding in place tissue parts or body parts of the patient. In the case of orthopedic operations in particular, such assisting activities frequently require the exertion of considerable force, which can exceed the capacities of human assistants but which, in contrast, a robot can apply for an indefinite period without tiring or diminishing in its precision. Advances in automatic speech recognition make it possible for such a robot to respond to spoken instructions by the operating surgeon in a similarly reliable way to human assistants. However, here too it must be ensured that an inappropriate movement on the part of the robot cannot injure the patient. A collision with the robotic arm and the possibility of a resulting injury to the patient should also be reliably ruled out before and after the operation, when transporting a patient to and from the operating and/or preparation room.
The prior are discloses a surgical robot system that comprises a multiple-axis articulated arm robot which carries an x-ray device and a collision-monitoring unit which warns of an impending collision between components of the x-ray device and a patient support arrangement or a patient laid thereon and/or prevents a collision.